Alfven/Ion-Cyclotron Waves Observed on the Earthward Side of a Solar Wind Reconnection Exhaust?
Abstract
We present an analysis of a solar wind reconnection exhaust observed by Wind and ACE on 19 January 2006 when Wind encountered five complete ~13-s period Alfvenic fluctuations on the Earthward side of the event. ACE only partially observed this activity despite its general proximity to Wind. The exhaust was characterized by accelerated plasma flow, a magnetic field depression and enhanced density and temperature. It was generally confined to the YZgse plane with a mostly sunward directed normal of the original current sheet. We explore whether the upstream Alfvenic fluctuations are consistent with standing ion-cyclotron waves formed at the interface between the Earthward propagating reconnection exhaust at Wind and the unperturbed solar wind where B=5.4 nT and Omega_ci=0.52 Hz or T_ci=12.2 s. Cluster and Geotail both observed the same solar wind current sheet as Wind and ACE encountered. However, Cluster observed enhanced magnetic field fluctuations at a higher 0.3-180 Hz frequency (5 ms to 3 s) and centered at the magnetic field depression rather than offset toward the Earthward side of the event. This high-frequency activity may be related to the reconnection exhaust which was unresolved by the Cluster-3 CIS instrument.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2009
- Bibcode:
- 2009AGUFMSH12A..03E
- Keywords:
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- 2109 INTERPLANETARY PHYSICS / Discontinuities;
- 2134 INTERPLANETARY PHYSICS / Interplanetary magnetic fields;
- 7835 SPACE PLASMA PHYSICS / Magnetic reconnection;
- 7836 SPACE PLASMA PHYSICS / MHD waves and instabilities